The FTSE 100 was up 0.2 percent at 7,446.84 points by 0920 GMT, having hit a fresh high of 7,460.20 points at the open.
Mining stocks, which have heavy representation in the FTSE 100, also rose. It ended the day at a record closing level of 7,454.37.
The pan-European STOXX 600 index was down 0.1 percent, and Germany's DAX traded flat.
"Investors seem to be feeling confident about the outlook for Britain under what is expected to be the biggest Conservative Party majority since Margaret Thatcher".
On the foreign exchanges, the pound lost ground after the release of the latest United Kingdom inflation figures.
CPI rose to 2.7% last month as the Brexit-hit pound, electricity price hikes and rising air fares tightened the squeeze on consumer spending.
In oil markets, Brent crude prices extended major gains made a day earlier, rising 0.2% to 51.87 USA dollars (£40.17) per barrel.
Kim sets mark at Players
It's their Players Championship. "If you can do that around this golf course, I mean you can out score everyone", he explained. He played tough, mature golf, didn't record a pageant score and is now forever a victor of one of golf's biggest events.
"Extending the cuts until March 2018 would take account of the fact that demand in the first quarter of a year is lowest for seasonal reasons", said Carsten Fritsch, analyst at Commerzbank. Hong Kong shares gained 0.9 per cent and their mainland equivalents 0.4 per cent, after Beijing soothed market fears of tighter regulation saying bank risks were "completely controllable".
And budget airline Easyjet posted a £236m loss for the six months to the end of March compared to £18m in the same period past year.
Crest Nicholson fell 16.5p to 620p.
Average selling prices were up 12% in the six months to the end of April from the same period a year ago at £418,000, while forward sales at the end of April were 5% ahead of last year, supported by an increase in outlet numbers.
In the currency markets, sterling is down against the dollar to $1.2909 and slipped 0.5% against the euro to €1.1690.
The biggest afternoon risers in the FTSE 100 Index were Vodafone (+8.1p to 219.2p), Ashtead Group (+33p to 1640p), Kingfisher (+6.1p to 355.1p), Reckitt Benckiser (+108p to 7471p) and British American Tobacco (+78p to 5472p).
Gains among oil stocks, however, were offset by a fall in healthcare shares, which were dragged by a 1 percent decline in Novartis.